Corona wires are utilized to generate a static electric charge to attract and repel toner from paper and to control the direction of travel of paper passing through personal computer printers and xerographic copiers. The heat generated in the toner fusion process and the harsh chemical environment in the machine eventually degrades the wires and they must be replaced if they are to adequately perform their job. Corona wires are mounted on removable frames and in various recyclable cartridges used in laser printers and copiers. As the cartridges are recycled, the corona wire will be replaced, if necessary. In certain instances, the corona wire is stretched between two rivets inserted in hollow plastic posts on the cartridge. In other cases, the corona wire is strung around a grid of such posts. In either case, once the distal end of the corona wire is fastened to a mounting post, it must be kept taught as it is strung across the space between mounting posts or as it is strung around various posts on a grid.
Various means of dispensing wire filaments have been developed. U.S. Pat. No. 5,062,580 discloses a spool with a resilient tab for storing and dispensing filament material. U.S. Pat. No. 5,672,871 discloses a corona wire handling device. U.S. Pat. No. 5,424,540 discloses a corona charger wire tensioning mechanism. U.S. Pat. No. 3,612,427 discloses a filament dispenser. A filament dispenser made of plastic includes a generally hollow cylindrical housing having a closed base on one end of the cylindrical housing and an open top on the other. The hollow cylindrical housing is sized sufficient to put a spool of filament therein, and a central threaded mounting post extends through the bottom wall of the housing, through the open central bore of the spool, and includes a threaded thumb screw on top of the spool. Filamentary wire from the spool is extended outwardly of the dispenser through a circular aperture in the cylindrical side wall. A hollow conical dispensing nozzle provides an exit for the filament. While the filament dispenser may be held in the palm or fingers of a user, both the thumb and first index finger are needed to turn the thumb screw to put pressure on the spool in order to maintain tension on the corona wire. The use of a single digit to turn the thumbscrew is unstable. The need for the use of multiple digits to operate the thumb screw degrades optimum usability of the filament dispenser.
A need has developed for an improved filament dispenser which may be more easily and simply manipulated by a user to string filament between a pair of poles, or around multiple poles in a grid while maintaining tension on the filament wire.